The present invention relates to an organopolysiloxane microemulsion, a process for its production, and a fiber-treatment composition based on said organopolysiloxane microemulsion. More specifically, the present invention relates to a microemulsion of organopolysiloxane having difunctional and trifunctional organosiloxane units, to a process for the production of such a microemulsion, and to a fiber-treatment composition which is based on said microemulsion.
With regard to emulsions of organopolysiloxane having difunctional and trifunctional organosiloxane units (below, referred to as di/tri organopolysiloxane), Japanese Patent Application Laid Open Number 54-131661 (131,661/79) describes such emulsions obtained by the emulsion polymerization of cyclic organosiloxane and functional group-containing organotrialkoxysilane.
Furthermore, fabrics made from natural fiber such as cotton, flax, silk, wool, angora and mohair; regenerated fiber such as rayon and bemberg; semisynthetic fiber such as acetate; or synthetic fiber such as polyester, polyamide, polyacrylonitrile, polyvinyl chloride, vinylon, polyethylene, polypropylene, spandex, and, among the long-fiber weaves in particular, taffeta, twill, Georgette, gauze, etc., with their especially coarse textures, readily undergo slip due to yarn separation. As a consequence, thermosetting resins such as epoxy, melamine, glyoxal, etc.; thermoplastic resins such as acrylic, etc.; latexes such as natural rubber, styrene/butadiene, etc.; and colloidal silica, among others, have been used as slip inhibitors.
However, the emulsions of di/tri organopolysiloxane known in the art consist of organopolysiloxane emulsions having average particle sizes of at least 0.3 microns, and accordingly, the stability (mechanical stability) with respect to the processes necessarily encountered in fiber treatment (agitation, circulation, expression of the treatment bath, etc.), the stability (dilution stability) against dilution (for example, 20-fold to 100-fold dilution with water). and the stability (blending stability) with regard to use with additives are all unsatisfactory. As a consequence, such an emulsion undergoes de-emulsification, and the organopolysiloxane floats to the top of the treatment bath. It will then appear as oil drops (oil spots) on the fibrous material, thus generating the serious problem of "staining."
Furthermore, because the stability (mechanical stability) with respect to the processes necessarily encountered in release agent applications (agitation, circulation, etc.), the stability (dilution stability) against dilution (for example, 20-fold to 100-fold dilution with water), and the stability (blending stability) with regard to use with additives are all unsatisfactory, such emulsions undergo de-emulsification and the organopolysiloxane separates. This adheres to the surface of the molding, creating the serious problem of oil spots.
When fiber is treated with a thermosetting resin (e.g., epoxy, melamine, glyoxal, etc.), thermoplastic resin (e.g., acrylic, etc.), or a latex (e.g., styrene/butadiene, natural rubber, etc.) in order to equip fibrous material with slip resistance, slip resistance is in fact obtained, but the hand becomes particularly stiff. Furthermore, the use of colloidal silica suffers from the problem of sedimentation of the colloidal silica unless this particular process is carried out at low temperatures for short periods of time with strict management of the pH of the treatment bath.